William bushnbll



WILLIAM BUSHNELL, OF NEW YORK, N. Y.

HAND-DRILL.

Specification of Letters Patent No. 8,554', dated December 2, 1851.

T0 all whom t may concern Be it known that I, WILLIAM BUsHNELL, of thecit-y, county, and State of New York, have invented certain new anduseful Improvements in DrillingfMachines; and Ido hereby declare thatthe following is a full, clear, and exact description of the same,reference being had to the accompanying drawings, forming part of thisspecification, in which- Figure 1 is an isometrical view of one of myimproved machines; Fig. 2: is a vertical section of the same. Fig. 3; isa plan or top view of the opening and closing nut or screw nippers. Fig.4c, is a sectional view showing the manner of adjusting the movablehead.

Similar letters of reference indicate corresponding parts in each of theseveral figures.

My invention consists in the employment for the purpose of giving thenecessary pressure to the drill, of a helical spring coiled around thedrill shaft and suitably confined and having its pressure controlled bymeans of a male screw on the said shaft and a nut suitably placed andformed in two part-s or in the two jaws of` a pair of nippers, which caneither be closed upon the male screw o-r released from it at thepleasure of the operator, the nut when closed upon the screw enables thespring to be set up or enables the drill to be withdrawn from its workby turning the shaft, but when released from the screw allows the drillto be operated upon by the spring. l

To enable those skilled in the art to make and use my invention I willproceed to describe its construction and operation.

A is the foot plate of the machine which carries two parallel rods orstandards B, B, perpendicular to it, forming the guide frame forcarrying the adjust-able head. The adjustable head consists of a hollowcylinder or socket, C, having two ears, a, and, b, o-n each side whichare bored to fit the rods, B, B; in front of each of the upper ears, a,a, are a pair of small lugs, c, c, through which are inserted a pin, d,forming the `fulcrum of a small lever, e; to the upper end of this smalllever is jointed a catch tooth, h, which passes through the ear, a, andfits into either onev of a series of notches,

in the rods B B; between the lower end of the small lever and the ear isplaced a small spring, g, which always tends to force the catch tooth,h, into one of the notches f f, the catch tooth being in a notchprevents the ascent of the head but owing to the 'shape of its point andthe corresponding shape oftthe notches allows its descent.

D is the drill shaft having a socket at its lower end to receive thedrill E, it is parallelv from theupper end to, z', where there i is ashoulder and has a screw, j, part of the way along it, its upper partfits in thek upper end of the socket C and its lower part in the lowerend of the socket which is made larger between the ends to receive thehelical spring F which coils around the shaft and rests upon theshoulder, z', its upper end bearing against a shoulder, 7L', in theupper part of the socket, I, is a crank for turning the shaft.

Attached to the upper end of the socket and forming part of theadjustable head, is

a small frame, G, in which is a guide, C, for

the upper part of the drill shaft, at the back of this frame is an arm,m, t-he top of which stands flush with the top of the socket, C.

H H represent the nippers which lay flat on the top of the socket C andarm, m, being secured to the arm, m, by a screwed pin, n, which passesthrough their ends land serves for them to work upon. At opposite pointsin each jaw is cut the female screw which forms an opening and closingnut for the screw j. To one handle of the nippers is attached a springcatch, p, which catches into a recess in the opposite handle, and holdsthe nippers together when they are closed. In Fig. 3, the nippers areshown closed upon the screw, but in Fig. 1 they are represented open andthe drill shaft free.

The foot plate A may either be permanently secured by bolting to anysuitable foundation or may be secured in any suitable position by acramp or other fastening to the object to be drilled or to a bench ortable.

The operation of the machine is as follows. The work being placed underthe drill or the machine being attached or applied to its work it willbe necessary to adjust the spring to give what may be considered by theoperator a suitable pressure to the drill. This is done by closing thenippers, H, H, upon the screw, j, and turning the shaft until the springis suiiiciently contracted, the adjustable head is then brought to asuitable position on the guide rods or standards, B, B, to bring thepoint of the drill to the work, the nippers are then opened and theshaft left free, rotary motion is then given to the shaft in the properdirection, in which the drill cuts and the expansion or opening of thespring gives the necessary pressure to the drill, when the hole made bythe drill is of the required depth, the nippers are closed upon thescrew, y', and the shaft turned in the proper direction to raise orwithdraw it. In some instances where the hole tobe drilled might be ofgreat depth the opening of the spring might reduce its pressure so muchthat it might require to be contracted which can be done by merelyclosing thenippers upon the screw and turning the shaftin the properdirection to raise the drill, after which the adjustable head can belowered to bring the drill to its work. For drilling a numberof holes ofa moderate depth, where the machine can be used stationary, theadjustable head will not require any adjust.- ment after being yset tothe proper position for the first hole. When it is necessary to raisethe head, the catches, h, It, must be withdrawn by pressing on the lowerends of the levers, e, e, when the head is left free to slide upward.

What I claim as my invention and desire `to secure by Letters Patent is-S. H. WALES, O. D. MUNN.

